The problem for lawmakers is that the existing per-gallon gas tax has hit a point of diminishing returns, as Americans drive less and vehicles become more fuel efficient.
Economists and civil libertarians are concerned about the Oregon pilot project in large part because some mileage meters can track and record residents’ every vehicular move. Rick Geddes, a Cornell University professor, said the basic device is okay because it is simply attached to a vehicle’s computer, which cannot track locations.
However, Geddes said privacy concerns could resurface should governments expand the program and use SmartPhone or apps to track movements and reward motorists who avoid congested roads and drive during off-peak hours.
Mark Perry, a University of Michigan scholar, says the GPS or “black box” system is "particularly untenable.”"
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